Electric terminal plug



Aug. 11, 1936. w PETO 2,050,374

ELECTRIC TERMINAL PLUG Filed April 6, 1935 grwcwfor,

erate with such plugs.

Patented Aug. 11, 1936 PATENT OFFICE 2,050,374 ELECTRIC TERMINAL PLUG Joseph W. Peto, Cleveland, Ohio Application April 6, 1935, Serial No. 15,080

5 Claims. (01. 173361) This invention comprises improvements in the common type of electric terminal plug used for plugging circuit wires into connection with socket members such as customarily provided to coop- The objectof the invention is the production of .a plug of a type made in sections for the purpose of facilitating the connection of the terminals of the wires to the contact plates of the plug. The construction of the body portion of the plug of my invention is peculiar in that it is formed in sections in such a manner as to provide complete separation of the wires inserted in the plug and connected to p the terminal plates or contacts thereof.

In other words, each section of my plug is equipped with a terminal contact or plate of conductive substance such as brass, usually availed of, the customary wire'attachment screw associated with said plate, and formed with a socket or recess for facilitating access to the said screw, and a passage which leads from the recess to the outer extremity of the plug section for receiving the end portion of the Wire inserted in the section and held in place by the screw. In effect, the plug may be said to consist of complemental combination male and female members since each section is equipped with a lug projecting therefrom .adapted to extend into the socket or recess of the other section, whereby to completely insulate the said screws and portions of the contact plates with which they are engaged, from each other. The said lugs form a means for accurately positioning the sections in relation to each other as well as to perform the function above mentioned, the plug sections being equipped additionally with an interlocking rib and groove for the same purpose.

By the provisions of the construction of my invention there is obtained practically a shortcircuit-proof plug of especial advantage in this type of devices and the construction is simple and may be readily manufactured from the customary rubber, Bakelite, or other compounds used in producing terminal plugs on this class.

An understanding of the invention will be had upon reference to the accompanying drawing, in which- Figure 1 is a side elevation of a terminal plug embodying the invention.

Figure 2 is a view looking toward the end of the plug having the terminal contacts or members.

Figure 3 is an inside side elevation of one of the sections of the plug, dotted lines illustrating the portion of the terminal contact member which is embedded in said section wholly in respect to the portion received by thesection.

Figure 4 is a view similar to Figure 3, but showing the opposite section to that illustrated in Figure 3, the section of Figure 3 having an inter- 5 locking rib tobe reecived by the interlocking groove of the section shown in Figure 4.

Figure 5 is a cross sectional View taken about on the line 5-5, looking in the direction of the arrows. 10

Figures 6 and 7 are similar cross sections to Figure 5 except that they are taken on the lines 6-5 and 'l1, respectively, looking in the direction of the arrows.

Figure 8 is a detail perspective view of one of 1.5 the terminal contact members, the larger end of which is wholly embedded in the section of the plug by which it is carried, and only exposed at the portion where the attaching screw recess is located.

Describing my invention specifically, my plug comprises the usual body which is made up in two sections, A and B, as seen best in Figures 3 and 4. My plug may be made up of any suitable insulating substance such as customarily employed for devices of this type and known to those versed in the art. As seen in Figure 3, the section A is formed with a protuberant part or lug I adapted to enter the attachment screw recess 2 of the section B of Figure 4. Likewise the section A is formed with a recess 3 designed to snugly receive the. projecting lug 4 of the section B, when the two sections A and B have their flat inside faces placed in abutment with one another to form the complete plug. It is to be 5 noted that the terminal contact member 5 of each section A and B is of identically the same formation. It consists of a somewhat L-shaped plate, the narrow portion of which projects from the end of the plug section to which it is at- 4.0 tached, after the usual manner, so as to readily enter between the contact members of a socket or terminal such as suitably provided for cooperation with plugs of the nature of the invention.

Each contact member 5 at its larger end portion is embedded in the section of the plug which carries the same, so that said portion, as well as the entire body of the said member, in fact, lies in a plane a considerable distance from and parallel to the flat faces 6 of the plug sections as designated in Figures 2 and 5. Thus it is that the disposition of the contact members 5 so that they lie about midway between the outer curved face and the flat. face of each section affords a disposition of the two contact members of the two sections in positions very considerably apart so that a wall of insulation of considerable thickness is between these members, and, as will be seen later, is likewise between the wires which are connected therewith.

For each contact member 5, I provide an attachment screw 3, this screw being screwed into an opening in the contact member and into the body of the section A or B in which it is embedded, as the case may be. The plug of the invention is of somewhat tapering form, the larger end carrying the terminal members 5 and the smaller end is formed to receive the ends of the wires with which the plug is connected, said wires being designated 8. Having in mind that it is highly important to keep the wires 8 separated from each other as much as possible when connected to the plug parts, each section A and B is formed with a longitudinal passage or opening shown in dotted lines in Figures 3 and 4 at 9, and the end of each wire 8 is caused to be pushed into and through this opening from the small end of the plug section where it enters, until it passes into its terminal through recess 2 or 3, as the case may be. Whereupon, the extremity of the wire is bent around the screw '1 and the screw tightened in the usual manner.

It remains to be described that the section A is formed with an integral rib H] which projects slightly from the fiat inside surface thereof, as shown in Figure 7, and is received in a longitudinal groove H so that said rib assists in interlocking the sections together in proper alignment. In performing such function the rib I0 and the groove ll cooperate with the look i that enters the recess 2 and the lock 4 that enters the recess 3 of the mating sections A and B.

For attaching the sections A and B together I may avail of any suitable kind of fastening means, an ordinary screw l2 and nut l3 being employed, as seen in Figure 6 and in Figure 1, the head of the screw and the nut being preferably countersunk according to the ordinary practice in making this type of terminal plug.

From the foregoing it will be apparent that when the sections A and B are fitted together with their fiat inner faces abutting, the lugs l and 4 enter the recesses 2 and 3 respectively, and, in conjunction with the body material of the plug, provide a solid mass of insulating substance filling the outer portion of the recesses, and afford a considerable thickness of insulating body between the contact members 5, as is most clear upon reference to Figure 5 of the drawing. Moreover, the ends of the wires 8 are so disposed that they lie practically in planes spaced apart a distance equal to the distance between the inner sides of the contact plates 5. On this ac count the portions of the wires which are disposed in the passages 9 of the plug sections are spaced a distance almost equal to the space between the widely separated contact plates or terminal members 5.

The foregoing arrangement of the wires 8 and the contact plates 5, and the construction of the plug by which said parts are insulated from each other, is conducive to a highly eflicient plug wherein the possibilities of short-circuiting across the wires and members 5 is substantially eliminated or rendered a very remote contingency indeed. It is obvious that according to the construction of the sections of the plug they will fit together and be held in accurate juxta-position when secured by the fastening l2 and there is no likelihood of friction on the wires and covering insulation that would tend to wear and produce possibility of short-circuits.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent of the United States, is

1. A terminal plug of the class described, comprising mating sections having abutting faces, means for holding said sections together, terminal contact members embedded in said sections and spaced a substantial distance from said abutting faces, said terminal contact members being provided with the usual wire fastening screw, each section having a recess for exposing the wire attachment screw connected to the terminal member, the screw registering with said recess, and each section having a projecting lug adjacent its said recess, the said lug and recess of one section fitting the recess and lug of the other section when the abutting faces of said sections are brought into contact.

2. A terminal plug of the class described, comprising mating sections having abutting faces, means for holding said sections together, a terminal contact member embedded in each of said sections and spaced a substantial distance from said abutting faces, said terminal contact members being provided with the usual wire fastening screw, each section substantially surrounding the portion of its respective terminal contact member embedded therein, excepting for a portion of the section which is recessed for exposing the wire attachment screw connected to the terminal member, and each section having a projecting lug adjacent its said recess, the said lug and recess of one section fitting the recess and lug of the other section when the abutting faces of said sections are brought into contact, one of the sections being formed with a longitudinal rib and the other section having a groove to receive said rib for interlocking the sections together supplementing the action of the lug and recess members.

3. A terminal plug of the class described, comprising mating sections having abutting faces, means for holding said sections together, terminal contact members embedded in said sections and spaced a substantial distance from said abutting faces, said terminal contact members being provided with the usual wire fastening screw, each section having a recess for exposing the wire attachment screw connected to the terminal member, the screw registering with said recess, and each section having a projecting lug adjacent its said recess, the said lug and recess of one section fitting the recess and lug of the other section when the abutting faces of said sections are brought into contact, each section being provided with a passage spaced from the abutting face thereof and extending from a point adjacent one end of the section to a point entering the recess of said section.

4. A terminal plug of the class described, comprising mating sections, means for holding said sections together, each section consisting of a. body portion having a flat face to abut with the other section, a terminal contact member embedded in and substantially surrounded by the body of each section a substantial distance away from said face, a portion of each terminal contact member projecting from the end of its respective section, wire terminal fastening means attached to the contact member, each mating section comprising a recess and a projecting lug for enclosing said wire terminal fastening means wholly insulated within the plug when the sec- 75 tions are brought together in abutting relation, and each section having a passage located a substantial distance away from the said meeting face and leading to a point adjacent said wire terminal fastening means so that a wire may be passed through said passage and connected to said wire terminal means.

5. As a new article of manufacture, a terminal plug of the class described, comprising two mating sections, means for holding said sections together, each section including a terminal contact member embedded at one end in and substantially surrounded by the body of the section and the other end of said member projecting from an end of the section, said section having a flat meeting face from which the contact member aforesaid is substantially spaced, each section having a lug projecting therefrom near one end and a recess formed therein near said lug, the lug of one section being adapted to enter the recess of the other section, a wire terminal fastening part disposed in the recess of each section and connected to the terminal contact member, and each section having a passage leading from the recess thereof through the body of the section in spaced relation relative tothe meeting face and through which passage a wire may be passed so as to be connected with the wire fastening member.

JOSEPH W. PETO. 

